Technical Field
[0001] The present invention relates to an elevator apparatus allowing the deceleration
of a car at a time of emergency braking to be adjusted.
Background Art
[0002] In a conventional brake device for an elevator, the braking force of an electromagnetic
brake is controlled at the time of emergency braking such that the deceleration of
a car becomes equal to a predetermined value, based on a deceleration command value
and a speed signal (for example, see Patent Document 1).
[0003] Further, to prevent a rope from slipping on a drive sheave in an emergency stop,
Patent Document 2 discloses a brake device installed on a hoist. It comprises a braking
force energizing means, a braking force release means to release a braking force applied
to the brake drum, and a braking force control means to control the braking force
release means. When the speed of the car during emergency braking is over a specified
limit or the deceleration is less than a specified limit, the braking force control
means gives full braking force first, and when it receives a specific value, a weaker
braking force than the full braking force is given.
Patent Document 1: JP 07-157211 A
Patent Document 2: JP 07-242377 A
Disclosure of the invention
Problem to be solved by the Invention
[0004] In the conventional brake device as described above and a braking control device,
however, the basic operation of emergency braking and the control of a braking force
are both performed by a single braking force control unit, so it requires a long time
period to perform calculation for controlling the braking force. As a result, there
occurs a delay in generating the braking force.
[0005] The present invention has been made to solve the above-mentioned problem, and it
is therefore an object of the present invention to obtain an elevator apparatus allowing
the operation of emergency braking to be started more reliably and swiftly while suppressing
the deceleration at the time of emergency braking.
Means for solving the problems
[0006] An elevator apparatus according to the present invention includes: a car; and a brake
device for stopping the car from running. In the elevator apparatus, the brake device
in particular includes: a braking force generating portion for generating a braking
force; a brake opening coil for generating an electromagnetic force for cancelling
the braking force against the braking force generating portion; and a power shutoff
portion for shutting supply of power to the brake opening coil in response to a brake
actuation command. Also, the brake device particularly includes: a brake control portion
for monitoring a deceleration of the car and generating a deceleration reduction command
when the deceleration of the car becomes equal to or higher than a predetermined value;
and a current adjusting portion for supplying the brake opening coil with power while
adjusting an amount of current, in response to the deceleration reduction command,
the current adjusting portion being capable of supplying the brake opening coil with
power even when the supply of power to the brake opening coil is shut off by the power
shutoff portion.
Brief Description of the Drawings
[0007]
Fig. 1 is a schematic diagram showing an elevator apparatus according to Embodiment
1 of the present invention.
Fig. 2 is a schematic diagram showing an elevator apparatus according to Embodiment
2 of the present invention.
Fig. 3 is a schematic diagram showing an elevator apparatus according to Embodiment
3 of the present invention.
Fig. 4 is a schematic diagram showing an elevator apparatus according to Embodiment
4 of the present invention.
Best Modes for carrying out the Invention
[0008] Preferred embodiments of the present invention will be described hereinafter with
reference to the drawings.
Embodiment 1
[0009] Fig. 1 is a schematic diagram showing an elevator apparatus according to Embodiment
1 of the present invention. Referring to Fig. 1, a car 1 and a counterweight 2 are
suspended within a hoistway by a main rope 3. The car 1 and the counterweight 2 are
raised/lowered within the hoistway due to a driving force of a hoisting machine 4.
[0010] The hoisting machine 4 has a drive sheave 5 around which the main rope 3 is looped,
a motor 6 for rotating the drive sheave 5, a brake drum 7 as a brake rotational body
that is rotated integrally with the drive sheave 5 as the car 1 runs, and a second
brake portion body 9 for braking rotation of the drive sheave 5. The driving of the
motor 6 is controlled by a drive control portion 10 as an operation control portion.
[0011] The brake portion body 9 has a brake shoe 15 that is moved into contact with and
away from the brake drum 7, an armature 16 mounted on the brake shoe 15, a braking
spring 17 as a braking force generating portion for pressing the brake shoe 15 against
the brake drum 7, and a brake opening coil 18 disposed facing the armature 16 to generate
an electromagnetic force for opening the brake shoe 15 away from the brake drum 7
against the braking spring 17.
[0012] A brake switch 22 as a power shutoff portion is connected between the brake opening
coil 18 and a power supply 19. An adjustment switch 22a as a current adjusting portion
is connected between the brake opening coil 18 and the power supply 19 in parallel
with the brake switch 22.
[0013] The brake switch 22 is directly opened/closed depending on whether or not there is
a brake actuation command (including a normal braking command and an emergency braking
command). That is, when the brake actuation command is generated, the brake switch
22 is opened. When the brake actuation command is canceled, namely, when a brake opening
command is generated, the brake switch 22 is closed. The brake actuation command and
the brake opening command are generated by an elevator control portion including the
drive control portion 10. A normal open/close switch is employed as the brake switch
22.
[0014] The adjustment switch 22a is normally open. That is, the adjustment switch 22a is
open except when the deceleration (the absolute value of a negative acceleration)
of the car 1 becomes equal to or higher than a predetermined value. Employed as the
adjustment switch 22a is a switch allowing the amount of the current supplied to the
brake opening coil 18 to be adjusted, for example, an open/close switch capable of
chopping or a slide switch for continuously changing a resistance value. The following
description of Embodiment 4 of the present invention will be given as to a case where
the open/close switch is employed. However, in a case where the slide switch is employed,
the switch is slid to change the resistance value instead of being turned ON/OFF.
[0015] When the brake switch 22 is opened while the adjustment switch 22a is open, the supply
of a power to the brake opening coil 18 is thereby shut off, so the brake shoe 15
is pressed against the brake drum 7 by the braking spring 17. When the brake switch
22 is closed, the brake opening coil 18 is thereby supplied with a power, so the brake
shoe 15 is opened away from the brake drum 7.
[0016] The turning ON/OFF of the adjustment switch 22a is controlled by a brake control
portion 23. The brake control portion 23 is constituted by a microcomputer having
a calculation processing portion (a CPU), a storage portion (a ROM, a RAM, and the
like), and signal input/output portions.
[0017] The brake control portion 23 monitors a deceleration of the car 1 during the running
thereof regardless of whether or not there is a brake actuation command, and controls
an electromagnetic force generated by the brake opening coil 18, namely, an open/closed
state of the adjustment switch 22a such that the deceleration of the car 1 does not
become excessively high or low. The brake control portion 23 detects and monitors
the deceleration of the car 1 independently of the drive control portion 10. That
is, deceleration estimation information for measuring or estimating the deceleration
of the car 1 is directly input to the brake control portion 23 from a sensor or the
like instead of being input thereto from the elevator control portion.
[0018] Available as the deceleration estimation information is information from a hoisting
machine rotation detector for detecting rotation of the motor 6, a car position detector
provided on a speed governor, a return pulley rotation detector for detecting rotation
of a return pulley around which the main rope 3 is looped, a weighing device for detecting
a load within the car 1, a speedometer mounted on the car 1, an accelerometer mounted
on the car 1, an axial torque meter for detecting an axial torque of the drive sheave
5, or the like. Employable as the rotation detectors and the car position detector
are encoders or resolvers.
[0019] When the deceleration of the car 1 becomes equal to or higher than a predetermined
value, the brake control portion 23 generates a deceleration reduction command. In
response to the deceleration reduction command, the adjustment switch 22a supplies
the brake opening coil 18 with power while adjusting the amount of current, thereby
reducing the deceleration of the car 1. In this case, the adjustment switch 22a is
connected in parallel with the brake switch 22 and hence can supply the brake opening
coil 18 with power even when the supply of power to the brake opening coil 18 is shut
off by the brake switch 22.
[0020] A brake device in Embodiment 1 of the present invention has the brake portion body
9, the brake switch 22, the adjustment switch 22a, and the brake control portion 23.
[0021] In the elevator apparatus structured as described above, the adjustment switch 22a
for adjusting a braking force is disposed in parallel with the brake switch 22 in
a circuit, and the brake switch 22 is opened immediately in response to a brake actuation
command. It is therefore possible to cause the brake portion body 9 to perform braking
operation immediately without an operational delay when the brake actuation command
is generated.
[0022] It is also possible to continue the running of the elevator apparatus while keeping
the brake control portion 23 from performing the control of deceleration even when
there is a malfunction in the brake control portion 23.
[0023] Further, the brake control portion 23 detects and monitors the deceleration of the
car 1 independently of the drive control portion 10. It is therefore possible to improve
the reliability.
Embodiment 2
[0024] Reference will be made next to Fig. 2. Fig. 2 is a schematic diagram showing an elevator
apparatus according to Embodiment 2 of the present invention. Referring to Fig. 2,
a current limiter 27 is connected between the power supply 19 and the brake opening
coil 18 in series to the adjustment switch 22a and in parallel with the brake switch
22. The current limiter 27 limits the current flowing into the brake opening coil
18 through the adjustment switch 22a. Employed as the current limiter 27 is, for example,
a resistor. Embodiment 2 of the present invention is identical to Embodiment 1 of
the present invention in other configurational details and other operational details.
[0025] In the elevator apparatus structured as described above, the current limiter 27 is
employed to set the upper limit of the amount of the current supplied to the brake
opening coil 18 which can be controlled by the brake control portion 23, so only part
of a power-supply voltage is applied to the brake opening coil 18. Accordingly, it
is possible to suitably limit the amount of the control of the brake portion body
9 by the brake control portion 23.
Embodiment 3
[0026] Reference will be made next to Fig. 3. Fig. 3 is a schematic diagram showing an elevator
apparatus according to Embodiment 3 of the present invention. Referring to Fig. 3,
a forcible braking switch 26 is connected between the brake opening coil 18 and the
power supply 19 in series to the adjustment switch 22a and the current limiter 27
and in parallel with the brake switch 22.
[0027] The forcible braking switch 26 is normally closed. The forcible braking switch 26
is opened in response to an external signal. When the forcible braking switch 26 is
opened while the brake switch 22 is open, the control performed by the brake control
portion 23 is thereby invalidated, so the brake portion body 9 is forced to generate
a total braking force. Embodiment 3 of the present invention is identical to Embodiment
2 of the present invention in other configurational details and other operational
details.
[0028] In the elevator apparatus structured as described above, the forcible braking switch
26 is provided between the brake opening coil 18 and the power supply 19. It is therefore
possible to invalidate the control performed by the brake control portion 23 according
to need, and cause the brake portion body 9 to perform braking operation immediately.
Embodiment 4
[0029] Reference will be made next to Fig. 4. Fig. 4 is a schematic diagram showing an elevator
apparatus according to Embodiment 4 of the present invention. In this example, the
forcible braking switch 26 is disposed at the highest level of all the circuit elements.
That is, the forcible braking switch 26 is connected in series to the circuit including
the brake switch 22, the adjustment switch 22a, and the current limiter 27.
[0030] In the elevator apparatus structured as described above, it is possible to invalidate
both the control performed by the brake control portion 23 and the state of the brake
switch 22 according to need, and cause the brake portion body 9 to perform braking
operation immediately.
[0031] Although the brake control portion 23 is constituted by the computer in the foregoing
examples, an electric circuit for processing analog signals may be employed to constitute
the brake control portion 23.
[0032] Further, although the brake device is provided on the hoisting machine 4 in the foregoing
examples, it is also appropriate to provide the brake device at another position.
That is, the brake device may be a car brake mounted on the car 1, a rope brake for
gripping the main rope 3 to brake the car 1, or the like.
[0033] Still further, the brake rotational body is not limited to the brake drum 7. For
example, the brake rotational body may be a brake disc.
[0034] Yet further, the brake device is disposed outside the brake rotational body in the
foregoing examples. However, the brake device may be disposed inside the brake rotational
body.
[0035] Further, the brake rotational body may be integrated with the drive sheave 5.
[0036] Still further, the current adjusting portion may be provided in a system different
from a system provided with the power shutoff portion to make it possible to supply
the brake opening coil 18 with power regardless of the state of the power shutoff
portion. For example, the current adjusting portion may be connected to a power supply
different from the power supply 19 to which the power shutoff portion is connected.
[0037] Yet further, although only one brake device is illustrated in each of the foregoing
examples, a plurality of brake devices may be provided for a single brake rotational
body.
[0038] Although the brake control portion 23 monitors the deceleration of the car 1 regardless
of whether or not there is a brake actuation command in the foregoing examples, it
is also appropriate to input a brake actuation command to the brake control portion
23 and permit the control of the deceleration of the car 1 only when the brake actuation
command is generated.
1. An elevator apparatus, comprising:
a car (1); and
a brake device for stopping the car (1) from running,
wherein:
the brake device comprises:
a braking force generating portion (17) for generating a braking force;
a brake opening coil (18) for generating an electromagnetic force for cancelling the
braking force against the braking force generating portion (17);
a power shutoff portion (22) for shutting supply of power to the brake opening coil
(18) in response to a brake actuation command;
a brake control portion (23) for monitoring a deceleration of the car (1) and generating
a deceleration reduction command when the deceleration of the car (1) becomes equal
to or higher than a predetermined value; and
a current adjusting portion (22a) for supplying the brake opening coil (18) with power
while adjusting an amount of current, in response to the deceleration reduction command,
the current adjusting portion (22a) being capable of supplying the brake opening coil
(18) with power even when the supply of power to the brake opening coil (18) is shut
off by the power shutoff portion (22),
characterized in that:
the power shutoff portion (22) is a brake switch (22) connected between the brake
opening coil (18) and a power supply to be opened in response to the brake actuation
command;
the current adjusting portion (22a) is an adjustment switch (22a) connected between
the brake opening coil (18) and the power supply in parallel with the brake switch;
and
the adjustment switch (22a) is normally open.
2. The elevator apparatus according to Claim 1, further comprising an operation control
portion (10) for controlling operation of the car (1), wherein
the brake control portion (23) detects the deceleration of the car (1) independently
of the operation control portion (10).
3. The elevator apparatus according to Claim 1, wherein the brake device further has
a current limiter (27) for limiting a current flowing into the brake opening coil
(18) through the current adjusting portion (22a).
4. The elevator apparatus according to Claim 1, wherein the brake device further has
a forcible braking switch (26) connected in series to the current adjusting portion
(22a) to invalidate control performed by the brake control portion (23) in response
to an external signal and hence forcibly cause generation of a total braking force.
1. Aufzugvorrichtung mit:
einer Fahrkabine (1); und
einer Bremseinrichtung zum Stoppen einer Bewegung der Fahrkabine (1),
wobei die Bremseinrichtung aufweist:
einen Bremskrafterzeugungsabschnitt (17) zur Erzeugung einer Bremskraft;
eine Bremsöffnungsspule (18) zur Erzeugung einer elektromagnetischen Kraft zur Aufhebung
der Bremskraft entgegen dem Bremskrafterzeugungsabschnitt (17);
einen Energiezufuhr-Abschaltabschnitt (22) zur Sperrung der Energiezufuhr zu der Bremsöffnungsspule
(18) als Antwort auf einen Bremsbetätigungsbefehl;
einen Bremssteuerabschnitt (23) zur Überwachung einer Verzögerung der Fahrkabine (1)
und Erzeugung eines Verzögerungs-Reduktionsbefehls, wenn die Verzögerung der Fahrkabine
(1) gleich oder größer als ein vorbestimmter Wert wird; und
einen Strom-Einstellabschnitt (22a) zur Zufuhr von Energie an die Bremsöffnungsspule
(18), wobei ein Stromwert als Antwort auf den Verzögerungs-Reduktionsbefehl eingestellt
wird;
und wobei der Strom-Einstellabschnitt (22a) in der Lage ist, die Bremsöffnungsspule
(18) selbst dann mit Energie zu versorgen, wenn die Energiezufuhr zur Bremsöffnungsspule
(18) durch den Energiezufuhr-Abschaltabschnitt (22) gesperrt ist;
dadurch gekennzeichnet, dass
der Energiezufuhr-Abschaltabschnitt (22) ein Bremsschalter (22) ist, der derart zwischen
der Bremsöffnungsspule (18) und einer Energieversorgung angeschlossen ist, dass er
als Antwort auf den Bremsbetätigungsbefehl zu öffnen ist;
der Strom-Einstellabschnitt (22a) ein Einstellschalter (22a) ist, der zwischen der
Bremsöffnungsspule (18) und der Energiezufuhr parallel zu dem Bremsschalter angeschlossen
ist; und
der Einstellschalter (22a) normalerweise offen ist.
2. Aufzugvorrichtung nach Anspruch 1 ferner mit einem Betriebssteuerabschnitt (10) zur
Betriebssteuerung der Fahrkabine (1), wobei
der Bremssteuerabschnitt (23) die Verzögerung der Fahrkabine (1) unabhängig von dem
Betriebssteuerabschnitt (10) erfasst.
3. Aufzugvorrichtung nach Anspruch 1, wobei die Bremseinrichtung ferner einen Strombegrenzer
(27) zur Begrenzung eines durch den Strom-Einstellabschnitt (22a) in die Bremsöffnungsspule
(18) fließenden Stroms aufweist.
4. Aufzugvorrichtung nach Anspruch 1, wobei die Bremseinrichtung ferner einen Zwangs-Bremsschalter
(26) aufweist, der in Serie mit dem Strom-Einstellabschnitt (22a) angeschlossen ist,
um eine durch den Bremssteuerabschnitt (23) als Antwort auf ein externes Signal ausgeführte
Steuerung unwirksam zu machen und daher zwangsweise die Erzeugung einer Gesamtbremskraft
hervorzurufen.
1. Appareil d'ascenseur, comprenant :
une cabine (1) ; et
un dispositif de frein pour empêcher la cabine (1) de se déplacer,
dans lequel :
le dispositif de frein comprend :
une partie de génération de force de freinage (17) pour générer une force de freinage
;
une bobine d'ouverture de frein (18) pour générer une force électromagnétique permettant
d'annuler la force de freinage contre la partie de génération de force de freinage
(17) ;
une partie de coupure de puissance (22) pour couper l'alimentation en puissance à
la bobine d'ouverture de frein (18) en réponse à une commande d'actionnement de frein
;
une partie de commande de frein (23) pour surveiller une décélération de la cabine
(1) et générer une commande de réduction de décélération lorsque la décélération de
la cabine (1) devient supérieure ou égale à une valeur prédéterminée ; et
une partie de réglage de courant (22a) pour alimenter la bobine d'ouverture de frein
(18) en puissance tout en réglant une quantité de courant, en réponse à la commande
de réduction de décélération,
la partie de réglage de courant (22a) étant capable d'alimenter la bobine d'ouverture
de frein (18) en puissance même lorsque l'alimentation en puissance à la bobine d'ouverture
de frein (18) est coupée par la partie de coupure de puissance (22),
caractérisé en ce que :
la partie de coupure de puissance (22) est un commutateur de frein (22) relié entre
la bobine d'ouverture de frein (18) et une alimentation en puissance à ouvrir en réponse
à la commande d'actionnement de frein ;
la partie de réglage de courant (22a) est un commutateur de réglage (22a) relié entre
la bobine d'ouverture de frein (18) et l'alimentation en puissance parallèlement au
commutateur de frein ; et
le commutateur de réglage (22a) est normalement ouvert.
2. Appareil d'ascenseur selon la revendication 1, comprenant en outre une partie de commande
de fonctionnement (10) pour commander le fonctionnement de la cabine (1), dans lequel
la partie de commande de frein (23) détecte la décélération de la cabine (1) indépendamment
de la partie de commande de fonctionnement (10).
3. Appareil d'ascenseur selon la revendication 1, dans lequel le dispositif de frein
a en outre un limiteur de courant (27) pour limiter un courant circulant dans la bobine
d'ouverture de frein (18) à travers la partie de réglage de courant (22a).
4. Appareil d'ascenseur selon la revendication 1, dans lequel le dispositif de frein
a en outre un commutateur de freinage forcé (26) relié en série à la partie de réglage
de courant (22a) pour invalider une commande effectuée par la partie de commande de
frein (23) en réponse à un signal externe et par conséquent provoquer la génération
de manière forcée d'une force de freinage totale.